16 SEER A/C on older furnace

hvac

I am getting competing bids to replace two 16 year old builder grade air conditioning units. (3.5 + 4 ton).

One bid is for 14 SEER Carrier units (24ACC442A003) with final price $6,320.

The other bid is for 16 SEER Lennox units (EL16XC1) with final price $8,474.

The carrier tech also quoted 16 SEER unit but said that I would not see the efficiency unless I also replaced my furnace.

Is what the Carrier tech said true: That the 16 SEER units will not achieve 16 SEER without replacing the furnace?

I posted the following tweet to ask Lennox:
https://twitter.com/pottmi/status/868529151749304322

Best Answer

True...but it's true for the 14 SEER unit too. It's a package deal. The condenser, evaporator, coils, furnace, etc. all need to be replaced to achieve the SEER rating.

Remember, the SEER rating is the MAXIMUM that is achieved. Depending on the number of heating days verses the number of cooling days per year is important too. Typical savings usually is about $10 - $20 per month from 14 to 16 SEERs. (Even 21 SEER unit has a savings of only $50 - $75 per month.) So, if you're COOLING about 6 months a year, your savings is about $60 - $120 per year. (We don't recommend a 21 SEER rating because the unit is two stage, complicated and expensive to service.)

By the way, here the cost difference between 14 and 16 SEER is about $500 - $700. (Installation cost is the same.)

Other considerations: 1) Here, we heat most of the time, so we are concerned about the HSPF rating. 2) Warranty (actually, we like Trane, Lennox, Carrier equally. Also, I just heard about a recall on some Carrier units...be sure to verify this.) 3) A programable thermostat will save a lot.